Abstract: Two electric utility employees were working in a landfill gas compressor shed. The shed was 7.3 meters long, 6.4 meters wide, and 2.7 meters high. The relief valves for the methane gas installation vented inside the shed. Ordinary (non-explosion proof) electric equipment had been installed in the shed. A negative pressure ventilation system had been installed; however, it was compromised because the louvers were nailed shut. One of the two employees went into the shed to check a control panel, and then the second employee opened one of the two doors to enter the shed. Apparently, there was an ignitable concentration of methane in the shed, and the gas ignited. (The source of ignition was not identified.) Both employees later reported smelling a heavy gas odor just before ignition. The explosion severely burned the two employees, and they were hospitalized for their injuries. One was released soon after the accident, but the other was hospitalized for several days. The more severely injured employee remained out of work for an extra period of time because he also injured his shoulder when he tried to ram down the shed door to escape the burning building. (The doors opened inwards.) 0620